Buffer for looms



July 12, 1966 w. HAAG 3,260,282

BUFFER FOR LOOMS Filed April 27, 1964 2 Sheets-Sheet 1 Fig. 1

' July" 12, 1966 w. HAAG 3,260,282

. BUFFER FOR LOOMS Filed April 27, 1964 2 Sheets- Sheet 2 United States Patent 3,260,282 BUFFER FOR LOOMS Walter Haag, Weil der Stadt. Germany, assignor to Albert Haag KG, Weil der Stadt, Germany Filed Apr. 27, 1964, Ser. No. 362,871 Claims priority, applicatiogn Germany, May 7, 1963,

,072 6 Claims. (CL 139-161) The present invention relates to a buffer for looms, especially a shuttle check. For a proper functioning of the bobbin change, it is necessary to stop or check the shuttle in a certain position as smoothly as possible so that it will not be thrown back by the shuttle check.

Heretofore known hydraulic shuttle checks or buffers have the drawback that they are complicated in construc tion and rather expensive. Moverover, they require careful servicing, and their braking effect is dependent on the temperature.

The checking or tucking straps frequently employed in this connection require continuous observation and adjustment.

It is, therefore, an object of the present invention to provide a buffer which will overcome the above-mentioned drawbacks.

It is another object of this invention to provide a buffer or shuttlecheck which will brake the shuttle to the required extent but will not throw back the same.

It is still another object of this invention to provide a buffer as set forth in the preceding paragraphs, which will be adjustable as to its braking force.

It is a still further object of the present invention to provide a buffer or shuttle check as set forth in the preceding paragraphs, which will, for all practical purposes, avoid wear of the impact plate of the buffer.

Still another object of the present invention consists in the provision of a buffer for looms, especially for automatic looms, which simultaneously serves as end abutment for the picker stick.

These and other objects and advantages of the invention Will appear more clearly from the following specification in connection with the accompanying drawing, in which:

FIGURE 1 is a diagrammatic part-sectional side view of a butter system according to the present invention;

FIGURE 2 represents a further embodiment according to the present invention, which differs from that of FIG- URE l in that the buffer serves as abutment for the picker stick and is provided with cushioning means.

The buifer according to the present invention is characterized by a substantially circular air bellows with an impact plate on which the picker stick impacts. The buffer according to the present invention furthermore has an.

air opening which is adjustable as to its cross-section and which allows the butter to brake at the desired extent so as not to throw back the shuttle. Tests with various types of looms have proved that the buffer according to the invention meets the requirements remarkably well.

Referring more specifically to the drawing, the buffer shown therein comprises a hollow circular body 1 forming an air bellows which may, for instance, be made of a rubber elastic synthetic material selected from the group consisting of polyurethane elastomers. Body 1 has an approximately flat elliptical cross-section with a short axis S and a long axis L and with two openings 1a, 1b therethrough the axes of which substantially coincide with axis S. Openings in, 1b are confined by wall portions 7, 7a respectively the outer surfaces 1c, 1d of which form the end faces of body 1. The buffer also comprises an impact plate, generally designated P, which has a central portion 2 and an annular portion 3. Plate P is impacted upon by the picker stick 4.

3,260,282 Patented July 12, 1966 Inasmuch as both parts 2 and 3 consist of rubber elestic yieldable material, i.e. rubber elastic synthetic material, a snap button-like connection of parts 2 and 3 is possible without any difiiculties and without the employment of metallic members. The other side of the hollow body 1 is held by two circular plates 5 and 6 clamping therebetween the adjacent wall portion 7 of body 1. The two plates 5 and 6 are pressed against each other by a connecting screw or bolt 8 with a head 9 engaging plate 5, while a nut 17 mounted on the threaded outside of bolt 8 presses against the outside of plate 6. Bolt 8 has a longitudinal bore 9' leading into the interior of hollow body 1, and also has a transverse bore 10 through which air can enter and escape into and from hollow body 1 to the desired extent. The effective cross-section of transverse bore 10 may be varied by means of a screw 11 threadedly engaging a portion of the bore 9' and held in its respective adjusted position by a nut 18. In this way, the braking effect of the buffer may be varied.

The buffer is connected to the outer end of the sley 13 by means of a holding member 12. Bolt 8 is screwed into the holder 12 and held in its respective position by a nut 19. As will be evident from FIG. 1, the buffer may be adjusted in the impact direction by the distance x.

In order to be able v'tO increase the adjusting range of the total available cross-section for the escape of the air, the buffer may be provided with one or more additional air openings which are not adjustable and which always remain open.

For purposes of exactly fixing the end position of the shuttle, automatic looms are customarily provided with a small end buffer which, as a rule acts upon the buffer stick. The positions of the end buffer and of the buffer have to be adjusted always with regard to each other.

In addition to penforming its normal function, the buffer according to the present invention is able to serve as an end buffer. This means a simplification of the Work for the operator inasmuch as, for instance with progressive wear of the picker, only one element has to be adjusted as opposed to the normal two elements.

FIG. 2 shows a bulfer of the last-mentioned type. The central portion 2 of the impact plate P is provided with an extension 26 which is adapted to engage a recessed surface 5A of plate 5B. The central portion 2 is provided with two channels 27 which also in the end position of the buffer, permit a pressure equalization.

When the shuttle impacts upon the picker, a starting shock occurs inasmuch as, first, the picker and picker stick and the cover of the buffer have to be accelerated. It is desirable, with lossely wound weft bobbins, to cushion this starting shock. This has been made possible with the arrangement according to the present invention by providing a dish spring 28 which is connected to the annular portion 3 of plate P through the intervention of a stepped margial portion 29 (see FIG. 2).

The butler acconding to the invention may also be employed on the inside of the picker stick, i.e. for checking after the impact. When greater forces are to be absorbed, a bellows with correspondingly thicker walls is to be employed. This greater wall thickness will bring about that the bellows will sufiiciently quickly return to its searting position even when working with a considerably smaller air opening.

Inasmuch as the air bellows of the buffer according to the present invention is able not only to move in axial direction but also, to a certain extent, transverse thereto, no relative movement between the picker stick 4 and the impact plate P, P will occur during the compression of the buffer. This fact explains the rather surprising result that the impact plate P, P of the arrangement according to the present invention does, for all practical pur- 3 poses, not wear out even when used over a considerable period of time, as has been proved by tests, and that the impact plate P, P has a lifetime which is a multiple of the lifetime of all heretofore known buffers for looms.

The impact plate 2, 3 of the buifer may when correspondingly connected also consist of other material as, for instance of a high molecular low pressure polyethylene with a molecular weight within the range of from 1 to 2 millions.

It is, Olf course, to be understood that the present invention is, by no means, limited to the particular constructions shown in the drawing but also comprises any modifications within the scope of the appended claims. Thus, the members 5, 5A and 6, may advantageously also consist of drawn metal parts. When designed solid, as shown in the drawing, plate 6 may also consist of high molecular polyethylene with a molecular weight of from 1 to 2. millions.

What I claim is:

1. *In a buffer for looms: air bellows of yieldable elastic material, impact plate means connected to one side of said bellows to be impacted upon by a picker stick, said impact plate means comprising an inner member extending from the inside of said bellows to the outside thereof, said impact plate means also comprising an outer annular member engaging that portion of said inner member which protrudes outwardly lfrorn said bellows and is connected thereto, supporting means connected to the other side of said bellows for supporting the same, and conduit means communicating with the interior of said bellows and the outside thereof for permitting air to escape from and enter said bellows.

2. A buffer for looms, which includes: air bellows means, impact plate means connected to one side of said air bell-lows means for impact by a picker stick, holding plate means connected to said bellows means for supporting the same, and bolt means extending through said holding plate means and supporting the latter, said bolt means being provided with passage means therethrough leading from the outside bolt means into the interior of said bellows means for establishing communication between the interior of said bellows means and the atmosphere.

3. In a buffer [for looms: air bellows of yieldable elastic material, impact plate means connected to one side of said bellows to be impacted upon by a picker stick, supporting plate means connected to the other side of said bellows for supporting the same, a bolt secured onto said supporting plate means and provided with conduit means establishing communication between the interior of said bellows and the outside thereof for permitting air to escape from and enter said bellows, and holding means adjustably connected to said bolt and adapted to be connected to a sley for permitting adjustment of said buffer in the direction of the axis of said bolt.

4. A buffer lforlooms, which includes: elastic air bellows means, impact plate means connected to and movably supported by one side of said air bellows means for impact by a picker stick, normally stationary holding plate means connected to said bellows means and facing said impact plate means for supporting said bellows means, said impact plate means having an extension for abutment with said holding plate means in response to a certain move ment of said impact plate means toward said holding plate means, and conduit means communicating with the interior 04f said bellows means and the outside thereof for permitting air to escape from and .to enter said bellows means.

5. A buffer for looms, which comprises: a hollow circular body having an approximately fiat elliptical cross section with openings therethrough the axes of which are in alignment with each other and substantially coincide with the shorter axis of said elliptical cross-section, said openings'being confined by wall portions the outer surfaces of which form the end faces of said hollow body, the distance between said end faces being considerably less than the distance between those circumferential wall sunfaces of said elliptical cross-section which are located diametrically oppositely to each other in the longitudinal direction of the longer axis of said elliptical cross-section, said hollow body being of yieldable elastic material, impact plate means connected to one of said end faces and including means extending into the opening in said one end face for connection therewith, said impact plate means being adapted to be impacted upon by a picker stick, supporting plate means extending into the opening of the other end face and being connected thereto, bolt means supporting said supporting plate means and thereby said hollow body, said bolt means having passage means therein for establishing communication between the interior of said hollow body and the atmosphere, and holding means supporting said bolt means.

6. An arrangement according to claim 5, which includes yieldable dish spring means arranged in said impact plate means and slightly protruding therelfrorn outwardly in axial direction of said openings for engagement with a picker stick prior to said picker stick engaging said impact plate means.

References Cited by the Examiner UNITED STATES PATENTS 664,816 12/1900 Mills 139161 1,242,431 10/ 1917 Foster 267 2,989,301 6/1961 Johannsen 26765 MERVIN STEIN, Primary Examiner.

DONALD W. PARKER, Examiner.

H. S. JAUDON, Assistant Examiner. 

1. IN A BUFFER FOR LOOMS: AIR BELLOWS OF YIELDABLE ELASTIC MATERIAL, IMPACT PLATE MEANS CONNECTED TO ONE SIDE OF SAID BELLOWS TO BE IMPACTED UPON BY A PICKER STICK, SAID IMPACT PLATE MEANS COMPRISING AN INNER MEMBER EXTENDING FROM THE INSIDE OF SAID BELLOWS TO THE OUTSIDE THEREOF, SAID IMPACT PLATE MEANS ALSO COMPRISING AN OUTER ANNULAR MEMBER ENGAGING THAT PORTION OF SAID INNER MEMBER WHICH PROTRUDES OUTWARDLY FROM SAID BELLOW AND IS CONNECTED THERETO, SUPPORTING MEANS CONNECTED TO THE OTHER SIDE OF SAID BELLOW FOR SUPPORTING THE SAME, AND CONDUIT MEANS COMMUNICATING WITH THE INTERIOR OF SAID BELLOWS AND THE OUTSIDE THEREOF FOR PERMITTING AIR TO ESCAPE FROM AND ENTER SAID BELLOWS. 